The UIDAI, the authority that issues Aadhaar card, has said linking of UID (Unique Identity Number) with PAN, bank account and mobile SIMs, among others, is mandatory and deadlines are "valid and lawful" as of now.

SBI customers can login on the bank's online banking portal. Once logged in, the customer can access the link 'Link your Aadhaar number' under the 'My Accounts' section appearing on the left panel of the screen.

Aadhaar is to be compulsorily quoted for carrying out a number of important tasks. These range from investment in the Public Provident Fund (PPF), National Savings Certificate (NSC) and Kisan Vikas Patra (KVP) schemes to opening of a Post Office account.

The Unique Identification Authority of India (UIDAI) has explained whether it is mandatory for NRIs or OCIs (Overseas Citizens of India) holding accounts in India to get their Aadhaar card linked by the December 31 deadline.